'ByRef' parameter '<parametername>' cannot be used in a lambda expression

A lambda expression declared within a Sub or function cannot use any ByRef parameters of that Sub or function. For example, the following code will cause this error because the ByRef parameter n is used in the lambda expression.

'' Not valid. 
'Sub ExampleSub(ByRef n As Integer)

'    Dim lambda = Function(p As Integer) p + n

'End Sub

Error ID: BC36639

To correct this error

• Assign the ByRef parameter to a local variable, and use the local variable in the lambda expression, as shown in the following code:

  Sub ExampleSub(ByRef n As Integer)
  
      Dim temp = n
      Dim lambda = Function(p As Integer) p + temp
  
  End Sub
  

See Also

Concepts

Lambda Expressions